At ordinary temperatures, the electrical conductivity of semiconductors in $S/m$ (or $mho/m$) is in the range:

This question has Statement $1$ and Statement $2$. Of the four choices given after the Statements,choose the one that best describes the two Statements.
Statement $1$ : $A$ pure semiconductor has a negative temperature coefficient of resistance.
Statement $2$ : On raising the temperature,more charge carriers are released into the conduction band.

State the conductivity and resistivity of a semiconductor.

In which material is the energy band gap maximum?

Read the following statements carefully:
$Y:$ The resistivity of a semiconductor decreases with an increase in temperature.
$Z:$ In a conducting solid,the rate of collision between free electrons and ions increases with an increase in temperature.
Select the correct statement from the following:

In insulators,which of the following statements is correct regarding their energy bands?